Sharpening apparatus for cloth-cutting-machine knives



i H. MAIMIN- AND W]. MARSHALL.

SHARPENING APPARATUS FOR CLOTH CUTTING MACHINE KNIVES. APPLICATION FILED MAn.-22. 1917.

1,303,936. Patented May 20, 1919.

g attozmauj H. MAlMlN AND W. I. MARSHALL.

SHABPENING APPARATUS FOR cum: currma MACHINE KNIVES.

APPLICATION FILED MAR. 22.191].

Patented May 20, 1919.

2 SHEETS-SHEET 2.

,PNO10-LH'ND..WASHINGTON. 11cv UNITED s'rnrns PATENT OFFICE.

HYMAN MAIMIN, OF NEW YORK, N. Y., AND WILLIAM MARSHALL, 0F NEWARK, NEW JERSEY, ASSIGNORS TO H. MAIMIN 00., INGJ, A CORPORATION OF NEW YORK.

SHARPENING APPARATUS FOR CLOTH-CUTTING-MAGHINE KNIVES.

Specification of Letters Patent.

Patented May 20, 1919.

Application filed. March 22, 1917. Serial No. 156,686.

To all whom it may concern:

Be it known that we, HYMAN MAIMIN and WILLIAM J. MARSHALL, both citizens of the United States, said MAIMIN residing in the city, county, and State of New York and said MARSHALL residing in Newark, county of Essex, and State of New Jersey, have invented certain new and useful Improvements in Sharpening Apparatus for Cloth-Cutting-Machine Knives; and we do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same,

This invention relates to sharpening means for the knives of cloth cutting machines of the reciprocating-knife type, and has for its object to provide an apparatus to permit rapid and correct sharpening of the knife and particularly of the chopping edge thereof, when the knife is removed from the cloth cutting machine for any reason.

In sharpening the chopping edge of a knife of the kind described, it has always been found very difficult to properly incline the knife relative to the sharpening stone, and where either the knife or the stone is manually held the sharpening operation is tedious and of indefinite duration, the new edge is seldom uniform, and the result is generally unsatisfactory.

In accordance with the present invention, there is provided a sharpening means for the chopping edge of the knife and a knifeholder into which the knife may readily be placed and wherein it may be held in fixed and proper relation to the knife sharpening means during the sharpening operation. Preferably the holder is so constructed as to take knives of different sizes and has means for adjustably positioning the chopping edge of the knife so that this edge may be treated by the sharpening stones in a manner best suited to the particular work for which the knife is to be used.

The sharpening means employed consists essentially of a pair of sharpening stones so mounted that they may be caused to wipe alternately across the chopping edge of the knife when the knife is clamped in the holder. The particular mechanism for operating the stones here shown is constructed in accordance with the invention disclosed and claimed in a co-pending application Serial No. 161,196 filed April 11, 1917, by one Henry B. Batjer, and this actuating mechanism does not in itself form any part of the present invention. We have found that the best results are attained if the knife blade is so supported that its lower chopping edge is projected freely into the field of operation of the stones, so that it may be said to float in this field of operation, the blade being sufficiently flexible to permit its lower end to be deflected somewhat by the stones. The shank of the knife should be grasped firmly by the holder. Furthermore, the arrangement should be such that the blade may be more or less projected so that the stones may be made to act upon the edge either to form a sharp cutting corner or a rounded corner where the lower chopping edge of the knife meets the forward L slicing edge.

The invention will be more clearly understood from the following description, when taken in connection with the accompanying drawings illustrating the invention in its preferred forms.

In these drawings Figure l is a side elevation of an embodiment of the invention; Fig. 2 is a front elevation thereof; Fig. 3 is a view partly in elevation and partly in section showing another embodiment; Fig. 4c is a view of the same embodiment taken at right angles to Fig. 3 and Fig. 5 is a section on line 5-5 of Fig. 3.

In the embodiment illustrated in Figs. 1 and 2 a base 6 has a bracket 7 for supporting the knife sharpening means, and a standard 8 constituting a knife-holder, these two parts being in fixed relation to one another. The sharpening device 9 is of the type in which a handle such as the handle 9? is turned to bring two sharpening stones 9' alternately into sliding engagement with the opposite sides of the chopping edge of the knife properly positioned in the knifeholder, as illustrated in Fig. 1. A knife sharpening attachment of this eneral type is shown, for example, in Iatcnt No. 1,186,488 issued to Hyman Maimin on June 6, 1916. The particular form of the sharpening device here shown is a modification, in accordance with the disclosure of the above-mentioned application of Henry B. Batjer.

The standard 8 is vertically slotted as indicated at 10, within which slot the knife 12 isadapted to bevinserted, the standard being reducedin widthvand cut away as shown to provide upper and lower pairs of ears 8 and 8 Qneof the-ears 8 has a boss. 11 through which a knurled clamp-screw 13 is threaded, a knurled jam-nut 14 being threaded on the clamp-screw. A thumbscrew 15 is threaded up into the two: ears 8" so that the upper end ofthe screw may support the lower end of the knife. The screw 15 constitutes a vertically adjustable shelf upon which the edge 12 of the knife is adapted to rest when the knife is inserted in the slot 10* and clamped therein by means of the clamp-screw 13. This edge 12 of the knife is a blunt portion thereof which is never sharpened and is shielded from engagement with the fabric being cut bythe knife guiding channel in the knife standard of the cloth cutting machine. The shopping edge 12 of the knife extends between this section 12 and the straight slicingedge 12. The ears 8 are so formed that the entire chopping edge 12 and the lower portion of'the slicing edge 12 are exposed, when the lower end of the knife is supported on the upper end of the screw 15 to position the knife properly relative to the field of operation of the sharpening device 9. The

ears 8 are shaped as indicated at 8 to permit wiping strokes of the stones 9* toward and away from the plane of the knife blade and .of' maximum efiiciency. The portion of the slot 10 which is located between the ears 8 is of greater width than the thickness of the'knife, as shown clearly in the drawing, to project the chopping edge of the knife freely into the field of operation ofthe device 9 where it floats so that its lower edgemay be deflected somewhat by the stones knife.

When the knife is tobe mounted in the apparatus and sharpened, the knife is first arranged in place relative to the sharpening device 9, by inserting the knife blade in the slot 10, as indicated, to rest the blunt portion 12 of the knife on the upper end of the screw 15. Should further adjustment of the knife then be necessary, such adjustment may be 'had by turning the screw 15' as re quired. hen the knife is seated properly in the slot 10 and on the screw 15, the clampscrew 13 is tightened to rigidly hold the knife during the sharpening operation in the precise adjustment obtained as just described. It has been found that by this means the'knife may be readily adjusted for sharpening, and also to arrange the chopping'edge 12 thereof at the required angle to the paths of movement of the stones 9 either for shaping the chopping edge as inas they are wiped against the v dicated by the full line or as indicated by the dot and dash line of Fig; 1, while sharpening such edge. The rounded corner indicated by the dot and dash line is the edge-formation which the knife should have when used for cutting plush goods, the sharp corner indicated by the dotted line being generally used when cutting other fabrics.

As is well known, the knives of clothcutting machines are commonly provided in a plurality of different lengths. paratus of Figs. 1 and 2, the clamp screw 14 engages and holds an intermediate portion of the knife 12 which is spaced from the lower end of the knife the correct distance to properly position the chopping edge of the knife relative to the sharpeningdevice. The apparatus of Figs. 1 and 2 is thusadapted to receive and sharpen knives of varying lengths without any necessity for displacing the field of operation of the clamp screw 14 relative to the field of operation of the sharpening device.

Referring to Figs. 3, 4 and 5, a support 19 carries a bracket 2O -anda tubular standard 21 spaced a fixed distance from the bracket, the bracket supporting a 'sharpeningdevice 22' similar to the sharpening device 9 of Fig; 1. p v

The standard 21 has a shelf 23 extended toward the sharpening device 22 and arranged slightly below the field'of operation of the sharpening stones thereof. The-shelf 23 is provided with a groove 24 for receiving the blunt portion 12 of" the knife12. A vertical bar 25 is movable upand down in the standard 21, and there is provided a setscrew 26 for securing the bar 25 in any desired position of adjustment. The bar 25 is vertically slotted as indicated at 28, the slot 28 being in line with a slot 29 through the tubular standard" 21 an'd'withthe groove 24 in shelf 23. A knurled pivot-screw 30 is threaded in the bar 25', the shank of the screw forming apintle passing across theslot 28', so that it may lie within the fork usually found at theupper end of a knife of the character here referredto. Two knurled adjusting screws 31 are threaded in the bar 25 for engaging the rear edge 12 of the knife, one above the axis of the pivot screw 30 and the other below such axis.

The construction just described, while more complicated than that of Fig. 1, has the advantage that the apparatus may be readily adjusted and held by the set screw26 to position the pivot screw 30 so that the latter, by engaging with the forked upper end of the knife 12, provides a fixed center about which the knife may be swung to position it properlyto present one or another portion of its edge to the stones, of the sharpeningdevice. This positionhaving. been roughly arrived at the knife is closely adjusted and; fixed by manipulation of the fulcrum screws 31. i

It will be seen that this apparatus pro- In the ap v-ides a knife-holder adapted to receive a knife of any commercial length and permitting the easy adjustment of the knife to a fixed position with relation to the plane of the action of the sharpening stones, this position being in general such that the longitudinal axis of the knife is substantially tangent to the path of the stones at the point where they make sharpening engagement with the lower edge of the knife. It is then only necessary to rotate the handle 9 to im part to the knife a correctly sharpened edge. The conditions incident to the sharpening of the edge are thus substantially predetermined by the manufacturer of the apparatus and are not left to the individual judgment of the user; with the single exception that provision is intentionally made for adjusting the knife so that different portions of the edge may be presented to the predetermined action of the sharpening stones, in accordance with the particular Work for which the knife is to be used.

What we claim is:

1. In a device for sharpening the chopping edge at the end of a long straight knife for cloth cutting machines by means of sharpening stones adapted to move alternately over a curved path, the combination of a standard, and means for engaging and holding an intermediate portion of the knife at a point spaced from the lower end of the knife the proper distance to position the chopping edge relative to the sharpening device. 7

2. An apparatus of the kind described having a knife-sharpener and a support therefor and a knife-holder adapted to hold the knife with its blade clamped in the holder and its lower edge floating in the field of operation of the sharpener, said sharpener including a pair of sharpening stones, a mechanism for wiping them with sharpening pressure alternately across 0pposite sides of the knife edge to be sharpened and means for adjusting the knife in the holder to present one or another portion of its edge in sharpening relation to the said stones.

8. An apparatus for sharpening the chop ping-edge at the end of a straight knife for cloth cutting machines, comprising a knifesharpener and a knife-holder adapted to hold the blade of the knife with its said edge exposed in a predetermined relation to the sharpener, the knife-holder comprising a device for supporting the lower end of the knife and a device for clamping the knife to the holder as thus supported.

4. An apparatus of the .kind described comprising a base, a knife-holder positioned thereon and havin a shelf to support the lower end of the knife and an uprising standard adapted to clamp the blade of the knife and hold it with its lower edge substantially free, and a knife-sharpener supported in fixed relation to the knife-holder, whereby a knife fixed in the holder has the edge to be sharpened presented in predetermined relation to the knife-sharpener.

5. An apparatus of the kind described comprising a base, a knife-holder positioned thereon and havin lower end of the knlfe and an uprising standard adapted to clamp the blade of the knife and hold it with its bottom chopping edge substantially free, and a knife-sharpener supported in fixed relation to the knife-holder, whereby a knife fixed in the holder has its edge presented in predetermined relation to the knife-sharpener, and a set screw for ad j usting the knife in the holder to present one or another portion of its edge in like predetermined relation to the sharpener.

6. An apparatus for sharpening the chopping-edge at the end of a straight knife for cloth cutting machines, comprising a knifesharpener and a knife-holder adapted to hold the blade of the knife with its said edge exposed in a predetermined relation to the sharpener, the knife-holder comprising a device for supportin the lower end of the knife and a device or clamping the knife to the holder as thus supported, one of said devices being vertically adjustable relative to the other.

7. An apparatus of the kind described comprising a knife-holder having a clamp with a transverse pintle adapted to receive a notch at the upper end of the knife, and a shelf upon which the lower end of the knife is adapted to rest, the clamp being vertically adjustable with respectto the shelf to adapt the holder to knives of different lengths, and a knife-sharpener supported in predetermined relation to the holder.

8. An apparatus of the kind described comprising a knife-holder having a clamp with a transverse pintle adapted to receive a notch at the upper end of the knife and a a shelf to support the shelf upon which the lower end of the knife HYMAN MAIMIN. WILLIAM J. MARSHALL.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. 0. 

